Container capping machines for rotating caps onto containers are known in the art. Typically, container capping machines use discs or belts for rotating the caps in relation to the containers such that the caps are screwed onto the necks of the containers. In this manner, caps that have been loosely placed onto the necks of containers are rotated until they are tightly secured to the container.
In many industries, such as in the pharmaceutical industry, it is important that the caps are screwed onto the containers tightly, so as to prevent unwanted opening of the container which could lead to tampering or contamination of the contents of the containers. As such, there are requirements surrounding the minimum amount of torque that should be applied to the caps, in order to ensure that the caps are securely tightened onto the containers. In order to comply with these requirements, container capping machines must ensure that they apply at least the minimum required amount of torque to the caps. If the cap is not screwed onto the container tightly enough, then the container does not meet the imposed requirements and the container needs to be removed from the production line.
In light of this minimum torque requirement, it is common for container capping machines to include load cells that are in communication with the capping disks and/or belts for measuring the amount of torque that is applied to the caps as they are being secured onto the containers. An example of this type of arrangement is described in U.S. Pat. No. 7,325,369 to Luc Jalbert. However, a deficiency with this type of arrangement is that the load cell is coupled directly to the brake of one of the tightening belts. As such, if the capping arrangement is defective for any reason, the load cell will provide a faulty reading which could lead to caps that do not meet the minimum torque requirement being kept in the production line, and eventually making their way into consumer's hands.
In light of the above, there is a need in the industry for an improved container capping machine that alleviates, at least in part, the deficiencies of existing container capping machines.